HarmonyOS 鸿蒙Next 页面组件安全区域以及内容全屏区域伸展

可以参考如下步骤：

1、在EntryAbility.ets中的windowStage.loadContent方法中添加以下代码，设置全屏模式和全屏模式时导航栏、状态栏的可见模式

  let isLayoutFullScreen = true;
      let windowClass: window.Window | undefined = undefined;
      try {
        let promise = window.getLastWindow(this.context);
        promise.then((data) => {
          windowClass = data;

// 设置窗口的布局是否为沉浸式布局（true表示沉浸式布局；false表示非沉浸式布局。）
          windowClass.setWindowLayoutFullScreen(isLayoutFullScreen)
            .then(() => {
              console.info('Succeeded in setting the window layout to full-screen mode.');
            })
            .catch((err: BusinessError) => {
              console.error('Failed to set the window layout to full-screen mode. Cause:' + JSON.stringify(err));
            });


//设置窗口全屏模式时导航栏、状态栏的可见模式（需全部显示，该参数设置为['status', 'navigation']，不设置，则默认不显示）
          let names: Array<'status' | 'navigation'> = [];
          windowClass.setWindowSystemBarEnable(names, (err: BusinessError) => {
            let errCode: number = err.code;
            if (errCode) {
              console.error('Failed to set the system bar to be visible. Cause:' + JSON.stringify(err));
              return;
            }
            console.info('Succeeded in setting the system bar to be visible.');
          });
          console.info('Succeeded in obtaining the top window. Data: ' + JSON.stringify(data));
        }).catch((err: BusinessError) => {
          console.error('Failed to obtain the top window. Cause: ' + JSON.stringify(err));
        });
      } catch (exception) {
        console.error('Failed to obtain the top window. Cause: ' + JSON.stringify(exception));
      }

2、设置外层宽高和web的宽高，分别都是100%，实现全屏区域伸展

import web_webview from '@ohos.web.webview';
import business_error from '@ohos.base';
import router from '@ohos.router';

@Entry
@Component
export default struct WebPage {
  webviewController: web_webview.WebviewController = new web_webview.WebviewController();

  // private paramValue:WebParam = {url:'',title:""}


  aboutToAppear() {
    // 配置web开启调试模式
    web_webview.WebviewController.setWebDebuggingAccess(false);
    // const params = router.getParams() as WebParam; // 获取传递过来的参数对象
    // this.paramValue = params;

  }

  build() {
    Scroll() {
      Stack() {
        Column() {
          Image($r('app.media.ic_back'))
            .height('40vp')
            .width('40vp')
        }
        .onClick(() => {
          router.back();
        })
        .alignItems(HorizontalAlign.Start)
        .justifyContent(FlexAlign.Start)
        .margin({ top: '12vp' })
        .width('100%')
        .height('100%')
        .zIndex(99)

        Web({ src: 'https://developer.huawei.com/consumer/cn/', controller: this.webviewController })
          .onLoadIntercept((event) => {
            console.log('url:' + event.data.getRequestUrl())
            console.log('isMainFrame:' + event.data.isMainFrame())
            console.log('isRedirect:' + event.data.isRedirect())
            console.log('isRequestGesture:' + event.data.isRequestGesture())
            return false
          })
          .domStorageAccess(true)
          .width('100%')
          .height('100%')
          .zIndex(1)


      }

    }
    // .alignContent(Alignment.TopStart)
    .width('100%')
    .height('100%')
    .expandSafeArea([SafeAreaType.SYSTEM], [SafeAreaEdge.TOP, SafeAreaEdge.BOTTOM])

  }
}

参考文档：

1、‘https://developer.huawei.com/consumer/cn/doc/harmonyos-references-V13/js-apis-window-V13#setwindowlayoutfullscreen9’

2、'https://developer.huawei.com/consumer/cn/doc/harmonyos-references-V13/js-apis-window-V13#setwindowsystembarenable9